FDA Slaps Strictest Warning Label on Botox

Botox will now carry the Food and Drug Administration’s strictest warning for pharmaceuticals after the agency raised concerns over the risk of botulism last year, Bloomberg reports. The approval of a rival botulinum toxin for cosmetic purposes prompted the review. The toxin can cause muscle weakness and breathing difficulty, particularly in non-approved applications for muscle spasms. Botox-maker Allergan’s shares fell 3% on the news. (More Botox stories.)